Overview
The TLV431AID is a low-voltage, 3-terminal adjustable precision shunt regulator produced by Texas Instruments. It is designed to operate at lower voltages compared to traditional shunt regulators like the TL431. The TLV431AID features a reference voltage of 1.24V and can be adjusted to output voltages ranging from 1.24V to 6V using two external resistors. This device is ideal for applications requiring low-voltage adjustability and high precision, making it suitable for a wide range of industrial, automotive, telecommunications, and computing equipment.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Reference Voltage (VREF) | 1.24 | V |
| Output Voltage Range (VO) | 1.24 to 6 | V |
| Reference Voltage Tolerance at 25°C | 1% (TLV431A) | % |
| Typical Temperature Drift | 4mV (0°C to 70°C), 6mV (–40°C to 85°C), 11mV (–40°C to 125°C) | mV |
| Operational Cathode Current (IK) | 80µA (typical) | µA |
| Output Impedance (zKA) | 0.25Ω (typical) | Ω |
| Minimum Cathode Current for Regulation (IK(min)) | 55 to 80µA | µA |
| Off-State Cathode Current (IK(off)) | 0.001 to 0.1µA | µA |
| Operating Temperature Range | –40°C to 85°C (TLV431AID) | °C |
Key Features
- Low-voltage operation with a reference voltage of 1.24V.
- Adjustable output voltage from 1.24V to 6V using two external resistors.
- High precision with reference voltage tolerances of 1% at 25°C for the TLV431AID.
- Low operational cathode current of 80µA typical.
- Low output impedance of 0.25Ω typical.
- Ultra-small SC-70 package offering a 40% smaller footprint than SOT-23-3.
- Internal amplifier and reference provide sharp turn-on characteristics, making it an excellent replacement for low-voltage Zener diodes.
- No external capacitor required for stability, but can be used if desired.
Applications
- Adjustable voltage and current referencing.
- Secondary side regulation in flyback switching-mode power supplies (SMPSs).
- Zener replacement in various circuits.
- Voltage monitoring and comparator applications with integrated reference.
- Isolated feedback circuits for 3V to 3.3V switching-mode power supplies when used with an optocoupler.
Q & A
- What is the reference voltage of the TLV431AID?
The reference voltage (VREF) of the TLV431AID is 1.24V.
- What is the adjustable output voltage range of the TLV431AID?
The output voltage can be adjusted from 1.24V to 6V using two external resistors.
- What is the typical operational cathode current of the TLV431AID?
The typical operational cathode current is 80µA.
- What is the output impedance of the TLV431AID?
The output impedance is typically 0.25Ω.
- What are the common applications of the TLV431AID?
Common applications include adjustable voltage and current referencing, secondary side regulation in flyback SMPSs, Zener replacement, voltage monitoring, and comparator applications.
- Does the TLV431AID require an external capacitor for stability?
No, the TLV431AID does not require an external capacitor for stability, but one can be used if desired.
- What is the operating temperature range of the TLV431AID?
The operating temperature range is –40°C to 85°C.
- How does the TLV431AID behave in open-loop and closed-loop configurations?
In open-loop, it behaves as a comparator, and in closed-loop, it acts as a shunt regulator or error amplifier.
- What are the advantages of using the TLV431AID over traditional Zener diodes?
The TLV431AID offers sharper turn-on characteristics and higher precision, making it an excellent replacement for low-voltage Zener diodes.
- Can the TLV431AID be used in isolated feedback circuits?
Yes, the TLV431AID can be used in isolated feedback circuits for 3V to 3.3V switching-mode power supplies when used with an optocoupler.
